1. Technical Field
The present invention relates to a projector and a control method for a projector.
2. Related Art
Traditionally, a projector is known which picks up an image of a screen using an image pickup device such as CCD, detects the four sides of a screen frame from the picked-up image, and corrects a projection image according to the screen frame. JP-A-2006-60447 discloses a projector which, when only three or fewer sides of a screen frame are detected, estimates the side (s) that cannot be detected on the basis of the detected sides and corrects an image according to the screen frame.
However, in some cases where the aspect ratio of the screen frame is different from the aspect ratio of a projected image from the projector, the position of the side(s) that cannot be detected cannot be estimated (calculated) correctly and the projected image cannot be suitably corrected according to the screen frame. Particularly when an output image from the projector is a wide type with an aspect ratio of 16:10 (or 16:9) while the screen frame has an aspect ratio of 4:3 and the projection distance is short, the projected image cannot be suitably corrected and the projected image may spread out of the screen frame.